Some conventionally prepared food items include froth or foam. For example, cappuccino, milk shakes, and some soups may have froth or foam. While conventionally prepared food items may be considered preferable by some consumers, other consumers are increasingly demanding the convenience of consumer prepared instant food alternatives. In order to accommodate consumer preferences, manufactures have developed instant food products which give consumers the food products they demand from a convenient instant food product by developing instant food items which have the same or similar characteristics as conventionally prepared food items. One challenge for manufacturers is how to produce a food product having froth or foam from an instant food item.
One prior solution used to manufacture an instant food product which has froth or foam is through the use of powdered foaming compositions which produce foam upon reconstitution in a liquid. Foaming powder compositions have been used to impart froth or foamed texture to a wide variety of foods and beverages. For example, foaming compositions have been used to impart froth or foamed texture to instant cappuccino and other coffee mixes, instant refreshing beverage mixes, instant soup mixes, instant milkshake mixes, instant dessert toppings, instant sauces, hot or cold cereals, and the like, when combined with water, milk, or other suitable liquid.
Some examples of gas-injected foaming creamers which can be used to impart foam or froth are disclosed in U.S. Pat. No. 4,438,147 and in EP 0 458 310. More recently, U.S. Pat. No. 6,129,943 discloses a foaming creamer produced by combining a gasified carbohydrate with protein and lipid. Using this technology, it was possible to eliminate gas injection of the liquid creamer composition prior to spray drying.
EP 0 813 815 B1 discloses a foaming creamer composition which is either a gas-injected foaming creamer or a creamer containing chemical carbonation ingredients which contains in excess of 20% protein by weight. The powder described has as essential ingredients, protein, lipid and filler material, the filler especially being a water-soluble carbohydrate. The high content of protein is needed to obtain a whipped cream-like, tight foam having spoonability.
One prior foaming composition is provided by U.S. Pat. No. 6,713,113 which discloses a powdered soluble foaming ingredient comprised of a matrix containing carbohydrate, protein, and entrapped pressurized gas. However, powdered ingredients containing both carbohydrate and protein are susceptible to nonoxidative browning reactions that can adversely affect the appearance, flavor, and shelf life of packaged food products. These complex chemical reactions occur between proteins and carbohydrates, especially reducing sugars, to form polymeric pigments that can severely discolor and diminish the flavor quality of food products. It has been discovered that highly effective foaming compositions containing entrapped pressurized gas can be manufactured without the need to use both carbohydrate and protein ingredients. Browning can occur very rapidly at high temperatures commonly used in food processing and susceptibility to browning can limit the range of heating conditions used to produce foaming compositions of the type disclosed in the aforementioned prior art.
A possible solution could be the use of a substantially protein-only composition, as described in WO-A-2004/019699. However, the use of protein itself also poses some problems. More importantly, none of the disclosed examples in the published patent application are devoid of carbohydrate.
U.S. Pat. No. 6,168,819 describes a particulate creamer comprising protein, lipid, and carrier, in which more than 50% by weight of the protein is partially denatured whey protein, the partially denatured whey protein being from 40 to 90% denatured. The total protein content of the creamer is between 3 and 30% by weight, preferably between 10 and 15% by weight. The creamer is particularly suitable for foaming creamer compositions. The foaming creamer composition, when added to a brewed hot coffee beverage, produces a large amount of creamy semi-solid foam.
U.S. Pat. No. 6,174,557 describes an instant particulate dry mix composition that produces a cappuccino beverage having surface foam with a marbled appearance upon reconstitution in water. The dry mix composition is made by deaerating and subsequently freeze drying a coffee extract to produce granules having an outer surface layer which is rapidly soluble and a larger inner core layer which is slowly soluble. The product has a density of at least 0.3 g/cc.
U.S. Patent Publication No. 2003/0026836 discloses a method for forming tablets or powders of carbohydrate-based pharmaceuticals or foods which includes subjecting tablets or powders which comprise a beverage base such as soluble coffee, foamed powder, sugar and creamer to pressure and temperature to produce a tablet or powder with increased solubility or dispersability on contact with water. In addition, a method is disclosed which promotes the dissolution or dispersion of a tablet or non-foaming powder by subjecting the tablet or powder to pressurized gas so that gas is entrapped therein to promote dissolution or dispersion of the tablet or powder on contact with water. It is notable that all examples provided therein of chemically compounded soluble compositions are carbohydrate-based powder or tablet compositions containing protein. Improved dissolution of tablets containing entrapped gas is demonstrated in working examples therein. However, improved dissolution or dispersability of powders, foaming or non-foaming, containing entrapped gas is not demonstrated in any working example therein.
A disadvantage of these recent combinations, as well as of many prior products, is that both proteins and carbohydrates are present. More importantly, even art directed to forming substantially protein-only compositions, such as WO-A-2004/019699, fail to disclose a working example devoid of carbohydrate. The foaming composition of WO-A-2004/019699 that forms the basis of all working examples disclosed therein contains carbohydrate glycerol at a level of 5% by weight. In fact, none of the relevant prior art discloses a working example or any reduction to practice of a foaming carbohydrate composition devoid of protein. Proteins can react with carbohydrates, especially when heated. Most of the time these (Maillard) reactions lead to undesired coloring and/or formation of off-flavor. This type of reaction generally occurs during processing or manufacturing, when the product is kept at higher temperatures for some time and often if it is kept at higher temperatures for prolonged times. In most of the preparation processes for the products described in the documents discussed herein-above, and particularly in the preparation processes described in U.S. Pat. No. 6,168,819, a prolonged time at elevated temperatures is used to gasify the powders. Also, proteins typically are much more costly and typically have much lower solubility and much higher viscosity in water than carbohydrates used to manufacture powdered foaming compositions. Accordingly, use of proteins can cause processing problems and increase the cost of foaming compositions. For example, protein solutions, even carbohydrate solutions containing protein, might have to be prepared at much lower concentration in water to avoid excessive viscosity and permit spray drying. In addition, many proteins are also susceptible to loss of functionality or solubility when exposed to heat during processing or when contacted with acidic food ingredients such as coffee powders. Finally, the presence of proteins in powdered foaming compositions can reduce the solubility or dispersability of these foaming compositions, as well as the solubility or dispersability of other ingredients in mixtures containing these foaming compositions, when reconstituted in water or other liquid.
Although foaming coffee additives are available, there is still a need for a powdered protein-free soluble foaming composition which, upon reconstitution, exhibits a foam characteristic desired by true cappuccino beverage connoisseurs. For example, prior resulting cappuccino beverages lack sufficient foam, the foam dissipates too quickly or there is a combination of both. Further, since prior foaming coffee additives included both a carbohydrate and a protein component, people on restrictive diets wishing to avoid one of the two components would not be able to consume any of the prior foaming coffee additives. Accordingly, a foaming coffee additive comprising a powdered protein-free soluble foaming composition is desirable which provides foam characteristics of a conventionally made cappuccino beverage.